1. Field of the Invention
The present invention relates to an ATM (asynchronous transfer anode) exchange system, and particularly, to a centralized test apparatus for an ATM exchange system, capable of centrally monitoring and testing cells transferred through a given line or path of the exchange system, or measuring the traffic of the line or path.
2. Description of the Related Art
One of the methods of testing an ATM exchange system is a loop test. The loop test employs a test cell generator that generates a test cell. The test cell is looped by a loop unit and is guided to a target route in the exchange system. Thereafter, the test cell is received by a receiver, which checks the test cell to see whether or not the target route is sound.
This kind of loop test is disclosed in, for example, Japanese Patent Application No. H05-177822 "Loop Test Method of ATM Exchange System," No. H02-243841 "Conduction Test Method of ATM Exchange Channel," and No. H02-336400 "Loop Test Method."
In addition to the function of testing channel conductivity, the ATM exchange system must have an OAM function of monitoring the quality of connection in an ATM layer, The details of this function are being studied in ITU-T (previous CCITT), To monitor a line, it is usual to connect a measuring device to a digital signal cross connector (DSX) of the exchange system.
A console is used to enter various instructions to maintain and operate the exchange system. When testing a given line of the exchange system, the console is used to enter test conditions. Then, the cross connector that physically terminates subscriber optical fiber lines is manipulated to open the target line, and the measuring device is connected to the target line.
The console is usually far from the cross connector, and therefore, a maintenance person must come and go between them when inspecting a given line, In this way, the prior art is inconvenient for maintenance persons.
In addition, the prior art is slow and inefficient because disconnecting a target line at the cross connector and connecting the measuring device to the target line need a lot of manpower.